com.google.cloud.speech.grpc.demos.NonStreamingRecognizeClient.java Source code

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/*
 * Copyright 2016 Google Inc. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// Client that sends audio to Speech.NonStreamingRecognize via gRPC and returns transcription.
//
// Uses a service account for OAuth2 authentication, which you may obtain at
// https://console.developers.google.com
// API Manager > Google Cloud Speech API > Enable
// API Manager > Credentials > Create credentials > Service account key > New service account.
//
// Then set environment variable GOOGLE_APPLICATION_CREDENTIALS to the full path of that file.

package com.google.cloud.speech.grpc.demos;

import com.google.auth.oauth2.GoogleCredentials;
import com.google.cloud.speech.v1.AudioRequest;
import com.google.cloud.speech.v1.InitialRecognizeRequest;
import com.google.cloud.speech.v1.InitialRecognizeRequest.AudioEncoding;
import com.google.cloud.speech.v1.NonStreamingRecognizeResponse;
import com.google.cloud.speech.v1.RecognizeRequest;
import com.google.cloud.speech.v1.SpeechGrpc;
import com.google.protobuf.TextFormat;

import io.grpc.ManagedChannel;
import io.grpc.StatusRuntimeException;
import io.grpc.auth.ClientAuthInterceptor;
import io.grpc.netty.NegotiationType;
import io.grpc.netty.NettyChannelBuilder;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.DefaultParser;
import org.apache.commons.cli.OptionBuilder;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;

import java.io.IOException;
import java.net.URI;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Client that sends audio to Speech.NonStreamingRecognize and returns transcript.
 */
public class NonStreamingRecognizeClient {

    private static final Logger logger = Logger.getLogger(NonStreamingRecognizeClient.class.getName());

    private static final List<String> OAUTH2_SCOPES = Arrays
            .asList("https://www.googleapis.com/auth/cloud-platform");

    private final String host;
    private final int port;
    private final URI input;
    private final int samplingRate;

    private final ManagedChannel channel;
    private final SpeechGrpc.SpeechBlockingStub blockingStub;

    /**
     * Construct client connecting to Cloud Speech server at {@code host:port}.
     */
    public NonStreamingRecognizeClient(String host, int port, URI input, int samplingRate) throws IOException {
        this.host = host;
        this.port = port;
        this.input = input;
        this.samplingRate = samplingRate;

        GoogleCredentials creds = GoogleCredentials.getApplicationDefault();
        creds = creds.createScoped(OAUTH2_SCOPES);
        channel = NettyChannelBuilder.forAddress(host, port).negotiationType(NegotiationType.TLS)
                .intercept(new ClientAuthInterceptor(creds, Executors.newSingleThreadExecutor())).build();
        blockingStub = SpeechGrpc.newBlockingStub(channel);
        logger.info("Created blockingStub for " + host + ":" + port);
    }

    private AudioRequest createAudioRequest() throws IOException {
        return AudioRequestFactory.createRequest(this.input);
    }

    public void shutdown() throws InterruptedException {
        channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
    }

    /** Send a non-streaming-recognize request to server. */
    public void recognize() {
        AudioRequest audio;
        try {
            audio = createAudioRequest();
        } catch (IOException e) {
            logger.log(Level.WARNING, "Failed to read audio uri input: " + input);
            return;
        }
        logger.info("Sending " + audio.getContent().size() + " bytes from audio uri input: " + input);
        InitialRecognizeRequest initial = InitialRecognizeRequest.newBuilder().setEncoding(AudioEncoding.LINEAR16)
                .setSampleRate(samplingRate).build();
        RecognizeRequest request = RecognizeRequest.newBuilder().setInitialRequest(initial).setAudioRequest(audio)
                .build();
        NonStreamingRecognizeResponse response;
        try {
            response = blockingStub.nonStreamingRecognize(request);
        } catch (StatusRuntimeException e) {
            logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
            return;
        }
        logger.info("Received response: " + TextFormat.printToString(response));
    }

    public static void main(String[] args) throws Exception {

        String audioFile = "";
        String host = "speech.googleapis.com";
        Integer port = 443;
        Integer sampling = 16000;

        CommandLineParser parser = new DefaultParser();

        Options options = new Options();
        options.addOption(OptionBuilder.withLongOpt("uri").withDescription("path to audio uri").hasArg()
                .withArgName("FILE_PATH").create());
        options.addOption(
                OptionBuilder.withLongOpt("host").withDescription("endpoint for api, e.g. speech.googleapis.com")
                        .hasArg().withArgName("ENDPOINT").create());
        options.addOption(OptionBuilder.withLongOpt("port").withDescription("SSL port, usually 443").hasArg()
                .withArgName("PORT").create());
        options.addOption(OptionBuilder.withLongOpt("sampling").withDescription("Sampling Rate, i.e. 16000")
                .hasArg().withArgName("RATE").create());

        try {
            CommandLine line = parser.parse(options, args);
            if (line.hasOption("uri")) {
                audioFile = line.getOptionValue("uri");
            } else {
                System.err.println("An Audio uri must be specified (e.g. file:///foo/baz.raw).");
                System.exit(1);
            }

            if (line.hasOption("host")) {
                host = line.getOptionValue("host");
            } else {
                System.err.println("An API enpoint must be specified (typically speech.googleapis.com).");
                System.exit(1);
            }

            if (line.hasOption("port")) {
                port = Integer.parseInt(line.getOptionValue("port"));
            } else {
                System.err.println("An SSL port must be specified (typically 443).");
                System.exit(1);
            }

            if (line.hasOption("sampling")) {
                sampling = Integer.parseInt(line.getOptionValue("sampling"));
            } else {
                System.err.println("An Audio sampling rate must be specified.");
                System.exit(1);
            }
        } catch (ParseException exp) {
            System.err.println("Unexpected exception:" + exp.getMessage());
            System.exit(1);
        }

        NonStreamingRecognizeClient client = new NonStreamingRecognizeClient(host, port, URI.create(audioFile),
                sampling);
        try {
            client.recognize();
        } finally {
            client.shutdown();
        }
    }
}